CAS 50-NP , CAS50-NP

CAS50-NP Current Sensor: High-Accuracy, Fast-Response Industrial-Grade Current Measurement Solution

CAS50-NP Product Overview

The CAS50-NP is a compact closed-loop fluxgate current sensor from LEM, designed for precision electronic measurement of DC, AC, and pulsed currents in industrial applications. Utilizing closed-loop fluxgate technology, it supports bidirectional current detection, provides electrical isolation between the primary and secondary circuits, and operates from a single +5 V supply. The CAS50-NP features a PCB-mount design with three main pins and an integrated conductor layout, allowing accurate measurement of both small and large currents. Its compact structure and excellent performance make it an ideal choice for drives and inverters in industrial, new energy, and automotive electronics.

CAS50-NP Key Technical Advantages

2.1 Closed-Loop Fluxgate Technology – Precision & Stability

The CAS50-NP employs closed-loop fluxgate sensing, ensuring extremely low offset and gain drift. It can measure up to three times the nominal current (approx. 150 A), making it especially suitable for high-stability, high-accuracy applications that do not require reference voltage management. This technology, combined with closed-loop compensation, effectively resists external magnetic field interference, delivering high accuracy, high stability, and good noise immunity – meeting the stringent demands of high-power current monitoring.

2.2 Ultra-Fast Response & Wide Bandwidth

For protection circuits and control systems that require fast response, the CAS50NP achieves a response time as low as 0.3 μs, instantly capturing transient overcurrent, shortcircuit, and other abnormal current signals, giving your system valuable time for protection and reaction. With a wide bandwidth of up to 300 kHz (±3 dB), the sensor not only monitors power frequency currents steadily but also accurately captures high-frequency harmonics in variable frequency drives and switching power supplies – providing a solid basis for system performance analysis and optimization.

2.3 Enhanced Safety Isolation & EMC Immunity

The CAS50NP meets stringent insulation requirements: rated insulation voltage 1000 V_rms and insulation test voltage 4.3 kV_rms, suitable for standard industrial applications requiring high-voltage isolation. It also features 4 kV electrostatic discharge (HBM) tolerance and excellent dv/dt immunity, effectively suppressing interference caused by high dV/dt switching in inverters and power supplies – ensuring safe and reliable measurement signals.

2.4 Excellent Temperature Stability & UltraLow Power Consumption

With low offset and gain drift, the CAS50NP maintains high accuracy of ±0.8 % and linearity of ±1 % over a wide temperature range from -40 °C to +85 °C, eliminating extra calibration due to temperature fluctuations. It supports a supply voltage from 4.75 V to 5.25 V and draws only 20 mA quiescent current – extremely low selfheating reduces overall system thermal buildup and energy consumption.

2.5 Compact PCB Mounting Design

Optimized for PCB mounting, the CAS50NP features an integrated conductor layout with overall dimensions of only 21.91 mm × 16.5 mm × 13.4 mm, significantly saving board space. The package is compatible with LTS and LTSR series, making it easy to upgrade existing board designs while maximizing PCB space utilization. The housing is made of UL 94V0 rated insulating plastic, enhancing flame retardancy and ensuring longterm reliable operation in dense PCB environments.

CAS50-NP Technical Specifications

CAS50-NP Typical Applications